1. Field of the Invention
This invention relates to laminated glass structures. This invention particularly relates to laminated glass structures that can withstand severe impact.
2. Description of the Prior Art
Threat-resistant windows and glass structures are known. U.S. Pat. No. 5,960,606 (""606) and U.S. Pat. No. 4,799,376 (""376) each describes laminate windows that are made to withstand severe forces. In International Publication Number WO 98/28515 (IPN ""515), for example, a glass laminate is positioned in a rigid channel in which a resilient material adjacent to the glass permits flexing movement between the resilient material and the rigid channel. Other means of holding glazing panels exist such as adhesive tapes, gaskets, putty, and the like can be used to secure panels to a frame.
Prior art windows and glass structures capable of withstanding hurricane-force winds and high force impacts are not trouble-free, however. For example, when subjected to severe hurricane forces the flexing movement in the windows of IPN ""515, wherein glass flexes within a rigid channel, gradually pulls the laminate out of the channel resulting in loss of integrity of the structure. In ""376, the glass held against the frame can be broken and crushed, causing a loss of structural integrity in the window/frame structure.
In one aspect, the present invention is a glazing element comprising a transparent laminate and a supporting structure attached to the laminate, the laminate comprising at least one layer of glass bonded directly to an interlayer of a thermoplastic polymer having low haze, wherein the polymer is exposed in such a manner as to allow for attachment of the laminate to the supporting structure, and wherein the laminate is attached to the supporting structure by way of the polymeric interlayer.
In another aspect, the present invention is a process for fabricating a glazing element which includes a glass/thermoplastic polymer laminate in a supporting structure comprising the steps: forming the glass/plastic laminate by positioning a thermoplastic polymer interlayer between two glass plates, the polymer being exposed in such a manner as to allow for attachment of the laminate to the supporting structure; removing air from between the layers of glass and the interlayer; applying heat and external pressure to adhesively bond the glass plates to the interlayer; and, attaching the polymeric interlayer to the supporting structure.
In still another aspect, the present invention is a process for fabricating a glazing element which includes a glass/thermoplastic polymer laminate in a supporting structure comprising the steps: forming the glass/plastic laminate by positioning a thermoplastic polymer interlayer between two glass plates, the polymer being exposed in such a manner as to allow for attachment of the laminate to the supporting structure; removing air from between the layers of glass and the interlayer; applying heat, but not external pressure, to adhesively bond the glass plates to the interlayer; and, attaching the polymeric interlayer to the supporting structure.
In another aspect, the present invention is a glazing structure comprising a transparent laminate having two layers of glass, each glass layer having a tin-side and an air-side, wherein the glass layers are laminated together with a thermoplastic polymer interlayer between the two layers of glass in such a manner that the interlayer is self-adhered to at least one of the glass surfaces, and wherein the interlayer is an ionomer resin.